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Unprecedented Burning in Tropical Peatlands During the 20th Century Compared to the Previous Two MillenniaNARA Subscribed
Tropical peatland wildfire incidence has risen in recent decades, driven by drainage for land use and intensified by severe droughts with global climate change. These disturbances have altered vegetation structure, disrupted ecosystem functioning, and increased carbon emissions, particularly in Southeast Asia. However, the long‐term history and characteristics of wildfires in tropical peatlands remain largely unknown. Here, we...
The Holocene history of Australia's climate is surprisingly poorly understood. This is, in part, because of the relatively weak forcing of Holocene climate versus that of the late Pleistocene. However, it is commonly suggested that eastern Australia dried during the mid‐ to late‐Holocene and that this was in response to increased activity in the El Niño–Southern Oscillation (ENSO), in particular, the intensification of the El...
This research documents the paleoenvironmental evolution of Eighteen Mile Swamp on North Stradbroke Island (Minjerribah), Australia, from oscillating coastal lagoon into stable freshwater swamp over the last ca. 1600 years. We analyzed multiple sediment cores via physical description, acid sulfate soil assays, particle size analysis, diatom and pollen assemblages, photosynthetic pigment content, and Itrax XRF spectrometry, alo...
Australian subtropical vegetation and wetland response to fire, climate and nutrient availability during the HoloceneNARA Subscribed
The iconic sand dune systems of Minjerribah (North Stradbroke Island), in southeastern Queensland, Australia, host numerous lakes and swamps containing organic‐rich sediment deposits that record changes in climate, fire and surrounding vegetation. Palaeoenvironmental reconstructions from individual locations can provide insights into changes in the environment, but determining the regional extent of these changes is seldom pos...
Diatom–salinity thresholds in experimental outdoor streams reinforce the need for stricter water quality guidelines in South AustraliaNARA Subscribed
Water quality guidelines are an important tool for managing environmental pressures on freshwater streams, but guidelines are frequently set using conditions from reference sites that are assumed to be unimpacted. Using biological thresholds potentially provides a better foundation for guidelines. However, guidelines based on field observations alone may be compromised by confounding influences. This study used an outdoor stre...
Records of Australian palaeoclimate beyond the last glacial cycle are rare, limiting detailed analysis of long‐term climate trends and associated ecosystem responses. This study analyses a discontinuous pollen and charcoal record from Fern Gully Lagoon, North Stradbroke Island (Minjerribah), subtropical Queensland, Australia, which covers much of the last ~210 ,000 years. Climate variation is inferred from changes in vegetatio...
Effect of substrate type on diatom-based water quality assessments in the Mount Lofty Ranges, South AustraliaNARA Subscribed
Diatoms have been widely used in stream health assessments as they are highly sensitive to water quality. There is no standardised method for diatom-based stream health assessments causing many substrates, both natural and artificial, to be used. Few studies have investigated the impact of substrate type on diatom assemblages in streams with highly variable water levels. To determine if the substrate type affects these assessm...
Reduced rainfall drives biomass limitation of long‐term fire activity in Australia’s subtropical sclerophyll forestsNARA Subscribed
Aim To understand the long‐term drivers of biomass burning in the sclerophyll‐dominated forests of Australia. Location Swallow Lagoon, North Stradbroke Island, Queensland, Australia. Time period Last ca. 8 kyr. Major taxa studied Eucalyptus sensu lato, Leptospermum and Casuarinaceae. Methods High‐resolution pollen and charcoal analyses were undertaken on a ca. 8 kyr sediment record and compared with an independent quantitative...
Quantitative reconstructions of terrestrial climate are highly sought after but rare, particularly in Australia. Carbon isotope discrimination in plant leaves (Δ leaf ) is an established indicator of past hydroclimate because the fractionation of carbon isotopes during photosynthesis is strongly influenced by water stress. Leaves of the evergreen tree Melaleuca quinquenervia have been recovered from the sediments of some perch...
A diatom‐inferred record of lake variability during the last 900 years in Lützow–Holm Bay, East AntarcticaNARA Subscribed
Decadal–centennial‐scale climate variability in coastal Antarctica remains poorly understood due to the limited number of highly resolved, well‐dated records. We present a 900‐year, decadal‐scale reconstruction based on sedimentary diatoms from Lake Abi in Lützow–Holm Bay, East Antarctica. Hydrological change is inferred from diatom ecological preferences in conjunction with an existing regional training set and implies that l...
Palaeolimnology in eastern and southern Australian estuariesNARA Subscribed